Polypharmacy as a reason for misinterpreting laboratory results in the elderly.

Today, clinical biochemistry laboratories play increasingly significant roles in diagnosing patients, monitoring treatment responses, and making prognoses. Over the last 50 years, technological advances have greatly impacted laboratory medicine. The analytical performance of autoanalyzers has reached higher levels through continuous improvement processes. Nonetheless, the preanalytical phase, the most important source of error in laboratory processes, considerably affects clinical laboratory test results. In the preanalytical phase, both controllable and uncontrollable variables influence laboratory test outcomes. Medications are among the controllable variables. Drugs can affect laboratory test results in a dose-dependent manner. Some of these effects may be classified as expected, while others are unexpected. Additionally, laboratory test results may be more misleading due to increased drug interactions in the geriatric population. Polypharmacy is a concerning issue for the elderly. Older individuals are at a higher risk of adverse drug reactions (ADRs) because of metabolic changes and reduced drug clearance associated with aging; this risk is further heightened by the rising number of prescribed medications. The use of multiple drugs increases the potential for drug-drug interactions. These interactions can lead to significant changes in laboratory parameters. Polypharmacy affects different organ systems to varying degrees, subsequently altering laboratory values. Managing laboratory abnormalities in polypharmacy requires a systematic approach grounded in a comprehensive medication history, chronological correlation, clinical judgment, and interdisciplinary collaboration.